biostudies-literatureNakamura KJapan Society for the Promotion of Science8798https://www.ebi.ac.uk/biostudies/studies/S-EPMC8062581biostudies-literatureUnknown11(1)European foulbrood (EFB) caused by Melissococcus plutonius is a major bacterial disease of honey bees. Strains of the causative agent exhibit genetic heterogeneity, and the degree of virulence varies among strains. In bee larvae orally infected with the highly virulent strains, ingested bacterial cells colonize the larval midgut and proliferate within the sac of the peritrophic matrix (PM), a barrier lining the midgut epithelium. However, the barrier is degraded during the course of infection, and M. plutonius cells eventually directly interact with the midgut epithelium. As M. plutonius possesses genes encoding putative PM-degrading proteins (enhancin, a chitin-binding domain-containing protein and endo-α-N-acetylgalactosaminidase), we constructed PM-degrading protein gene-knockout mutantScientific reportsPeritrophic matrix-degrading proteins are dispensable virulence factors in a virulent Melissococcus plutonius strain.PMC8062581JP25292200JP17K08818Okumura KTakamatsu DOkamoto MNakamura KHarada MOkura MfalsePeritrophic matrix-degrading proteins are dispensable virulence factors in a virulent Melissococcus plutonius strain.European foulbrood (EFB) caused by Melissococcus plutonius is a major bacterial disease of honey bees. Strains of the causative agent exhibit genetic heterogeneity, and the degree of virulence varies among strains. In bee larvae orally infected with the highly virulent strains, ingested bacterial cells colonize the larval midgut and proliferate within the sac of the peritrophic matrix (PM), a barrier lining the midgut epithelium. However, the barrier is degraded during the course of infection, and M. plutonius cells eventually directly interact with the midgut epithelium. As M. plutonius possesses genes encoding putative PM-degrading proteins (enhancin, a chitin-binding domain-containing protein and endo-α-N-acetylgalactosaminidase), we constructed PM-degrading protein gene-knockout mutant2021-01-01T00:00:00Z2021 Apr2026-05-08T15:00:32.926Z2022-02-09T16:58:57.277ZS-EPMC80625813388883710.1038/s41598-021-88302-8